1. Field of Invention
This invention relates to routing apparatus utilizing a matrix of cross-point switches for directing any one or more of a number of electrical signals on a plurality of input channels to any one or more of a number of output channels. More particularly, it relates to such apparatus having a graphical interface displaying a pictorial representation of the matrix of cross-point switches from which selection of connections between input and output channels can be made. It has particular application to routing video and audio signals in the broadcasting, security and multi-media fields.
2. Background Information
Signal routers are used to switch signals on any one or more input channels to one or more output channels. Typically, such signal routers have a matrix of cross-point switches for selectively connecting the input channels with the output channels. Traditionally, signal routers have used mechanical switches or push buttons to make the interconnections. Such devices are hard-wired to the matrix terminals, and thus the configuration cannot be easily changed.
U.S. Pat. No. 5,144,548 discloses a computer-based routing switcher in which sophisticated switching functions are implemented easily through manipulation of icons on a display screen, preferably through the use of a touch screen or mouse input device. Computer software generates control signals for operation of the cross-point switches in response to the selection of source and destination icons on a display.
In the exemplary embodiment, the icons are arranged in a rectangular array on a screen, or pages of a screen when all of the icons cannot be accommodated on a single screen. Routing is implemented by selection of a source icon followed by selection of one or more destination icons. The selected icons, which may be located anywhere in the array of icons, all assume a unique color to identify the signal path. Multiple signal paths each have the associated source and destination icons identified by a unique color code. In this system, the switching matrix is transparent to the user.
Most of the source and destination devices connected to routers have multiple signals, thus a video camera can have four video channels and left and right audio channels, and a VCR can have a video channel and two audio channels. For such multiple channel devices, selection of the device icon switches all of the channels simultaneously. If some of the signals for a particular device are to be routed separately from others, a break-a-way menu is called up to effect the switching. The icons of devices having signals routed in different signal paths will be partly colored for each of the different signal paths.
The routing switcher of U.S. Pat. No. 5,144,548 provides a very flexible, easily used, routing switcher. The displays are organized to continuously present a comprehensive, easily understood, picture of switching functions which had been implemented.
For very large switches, there is a need for an improved routing switcher with a graphical interface which more easily assimilates the large amount of information available in such a system for presentation to the user. More particularly, there is a need for such a computer-based signal router with a graphical interface which more clearly represents the switching matrix, and especially a multi-signal switching matrix.
These needs and others are satisfied by the invention which is directed to a signal router having a display device which displays a pictorial representation of the matrix of cross-point switches. Input means, such as a mouse, a touch screen or a keyboard is used to select the cross-point switches in the matrix from the pictorial representation on the display device. The digital computer is programmed to generate control signals operating the cross-point switches selected from the pictorial representation through the input means to connect the selected source channels to the selected destination channels. In a preferred form of the invention, the display means displays the pictorial representation of the matrix of cross-point switches as a first pattern of generally parallel stripes representing an array of source channels, and a second pattern of generally parallel stripes representing an array of destination channels, with the two patterns of parallel stripes generally perpendicular to each other to form intersections representing the cross-point switches. A visual indicator is used to indicate cross-point switches which are closed.
Where at least some of the source and destination channels comprise multiple signals, corresponding signals for all channels are organized in separate logical signal planes, and separate cross-point switches are provided for each signal in each of the multiple signal logical planes. The display device includes means for selectively generating a symbolic representation for a selected signal plane and the computer is programmed to selectively generate control signals to operate selected cross-point switches in the selected signal plane and to generate indicators on the display device for the cross-point switches in the selected signal plane which are closed. Any of the separate signal planes can be displayed, or a composite symbolic representation representing a plurality of the signal planes, including all of the signal planes if desired, can be displayed. In this case, the visual indicators at the cross-points indicate separately which cross-point switches in each of the signal planes are closed. Identification of the signal planes can be enhanced by color-coding.